Press



PRESS Filed Oct. 19, 1935 7,. J 52! J 20 E L 5 y 29 IL I I4 2 2 a l 2,5 1"

f, IIHlf I IHI; 2 W

22 Inventor:

Clifford N. Benandh,

' His Attovneg.

Patented Nov. 1, 1938 UNITED STATES PRESS Clifford N. Benander, Meriden, Conn., assignor, by mesne assignments, to MonowattElectric Corporation, a corporation of Rhode Island Application October 19,

Claims.

The present invention relates to presses of the type suitable for producing molded parts.

The object of my invention is to provide an improved construction and arrangement in a press of this type, and for a consideration of what I believe to be novel and my invention attention is directed to the accompanying description and the claims appended thereto.

In the accompanying drawing, Fig. 1 is an elevation partly broken away of a press embodying my invention showingthe press in the open position; Fig. 2 is a fragmentary elevation showing the press in the closed position; Fig. 3 is a sectional view taken on line 33 of Fig. 1; and Fig. 4 is a perspective view of two of the links used to operate the press.

Referring to the drawing, the press is supported on a frame which comprises a base plate 5 supported by four columns 2. Tothe upper side of the base plate are secured four rectangular guide posts 3 to the upper ends of which is bolted a stationary platen 4. A movable platen 5 is arranged to slide toward and away from the stationary platen 4 on the guide posts 3. The adjacent faces of the stationary and movable platens are arranged to carry the complementary parts. 6 and l of a suitable mold.

As shown in Fig. 3, the movable platen 5 is of channel-shaped section having depending flanges 2.0 8 connected by a web portion 9. Adjacent the inner side of each of the flanges 8 are angular guides I9 having one side secured to a shoulder l l on the web portion 9 by screws I2 and having the other side contacting the inner surface of the adjacent flange. Below the guides H] are plates l3 which are secured to the lower edges of the flanges by screws It. The plates 13 and the guides l9 provide guides on the under side of the movable platen which are spaced apart in the direction of movement of the movable platen.

The link-age for reciprocating the removable platen comprises two. links l5 which are respectively pivoted at one end on pins I6 which are carried by brackets I! on opposite sides of the base plate l. The other end of each of the links l5 extends between the forked end 18 of a link I9 and is pivoted thereto by means of a pin 20. The other end 2| of each of the links I9 is also forked and is pivotally connected by a pin 22 to a block 23 fixed to the upper end of a piston rod 24. To the lower end of the piston rod is fixed a piston 25 which slides within a cylinder 26. The piston is reciprocated by fluid conducted from a source of fluid pressure by a supply conduit 26a selectively connected to conduits 26b 1935, Serial No. 45,760 (01. 18-16) and 260 connected respectively to each end of the cylinder. The supply of fluid is controlled by a four-way valve 26d which is arranged so that when fluid is supplied to one of the conduits 26b or 260 fluid is discharged from the other .of the conduits through a discharge conduit .266. Suitable packing 21 is arranged between the piston rod and the cylinder. The cylinder is supported on the columns 2 by a plate 28. The force for reciprocating the movable platen is transmitted to the movable platen through rolls 29 which project from opposite sides of the link l9 adjacent the pin 20. As shown by Fig. 3, these rolls extend between the parallel guides formed by the'guides l0 and the plates l3.

In the operation of the press, the linkage causes a gradual increase in leverage as the press moves from the open position shown in Fig. 1 to the closed position shown in Fig; 2. During the closing movement, the rolls 29 bear against the guides i0. At the start of the closing movement, the leverage ratio is substantially one to one, and the leverage gradually increases to a maximum as the links 19 approach a horizontal position, slightly above the position shown in Fig. 2. It is apparent from an inspection of Fig. 2 that there is a considerable range during which substantially the maximum leverage is exerted on the movable platen. This range extends from a position in which the links are slightly below the position shown in Fig. 2 to a position in which the links are inclined slightly above the horizontal. The press therefore accommodates itself to a rather large variation in stroke without adjustment and without substantial variation in pressure. On the reverse stroke, the rolls 29 bear against the plates l3 and the force exerted on the movable platen is the same as during the pressure stroke. This means that the maximum pressure on the press is available for separating the parts of the mold. This feature is of particular importance in the manufacture of parts from molded insulating material, since the force required to break the mold is substantially the same as the force required to press the parts of the mold together.

What I claim as new and desire to secure by Letters Patent of the United States, is:

l. A press for producing molded parts comprising a frame, a stationary platen, a movable platen slidable in the frame, complementary parts of a mold carried by said platens, a pair of guides on the movable platen spaced apart in the direction of movement of the movableplaten, a toggle including a pivoted lever having a member adj acent its pivot point slidable between said guides for reciprocating the movable platen, said member engaging one'of the guides during the pres- V sure stroke and the other guide during the re'- verse stroke of the movable platen, a piston for moving said lever to effect reciprocation of the movable platen, and fluid pressure means for positively reciprocating'the piston.

2. A press for producing molded parts comprising a frame, a stationary platen, a movable platen slidable in the frame, complementary pa'rtsf of a mold carried by said platens, a piston, two

links pivoted respectively at one end to opposite sides of the frame, two links each pivoted at one end to therpiston and at the other end to oneof said first links, members projecting from each side of said second links adjacent the pivotal connection between said first and said second links, parallel guides on said movable platen between which said members slide, said members engaging one of said guides during the pressure stroke of the piston and the" other of said guides during the reverse stroke of the piston, and fluid pressure meansfor positively reciprocating the .piston.

j I 3. A'press' for producingomolded parts comprising a frame,'astationary platen, a movable platen slidable in the frame, complementary parts of a moldcarried by saidiplate'ns, two links pivoted respectively at one end to opposite sides of the. frame, two links each pivoted at one end to one of said first links and havingthe other ends adjacent each other, means including a pistonfor reciprocating said other ends toward and away from the stationary platen, guides on the'movable platen spaced apart inthe'direction of movement of the movable platen, members on said second links adjacent the pivot points between the first gaging one of said guides during the pressure pressure means for positively reciprocating said piston. e

4. A press for producing molded parts comprising a frame, a stationary platen, amovable platen slidable in said frame, complementary parts of a mold carried by said platens, said movable platen having depending flanges connected by a web portion, guides on the web portion adjacent each of the flanges, plates secured tothe flanges extending over said guides, a lever having meme for reciprocating the movable platen, said'mem bers engaging said guides during the pressure stroke and saidplates during the reverse stroke of the movable platen, a piston for moving said and fluid pressure means for positively reciprocating the piston. 7 i

5. Apr'ess for producing molded parts comprisingaframe, a stationary platen, a movable platen slidable in said frame, complementary 10 be rs slidable between said guides and said plates lever to effect reciprocation of the movable platen, r

parts of amoldcarried'by said platensjsaid movable platen having depending flanges connected by a web portion, a pair of guides adjacent the inner surface of each of the flanges, said guides being spaced apart in the direction of movement of the movable platen, two links pivotedre'spectively at one end to opposite sides of the frame,

two links each pivoted at one end to said first links and, having the other ends adjacent each other, means includinga piston for reciprocating said other ends toward and away from the stationary platen, members projecting from opposite sides of said "second links between said pairs ofguides for a 'moving the movableplaten, saidmembers engaging the guides adjacent the web portion of the movable platen during the pressure stroke and engaging the other guides during the reverse stroke or the movable platen, and fluid pressure means for positively reciprocating said piston.

CLIFFORD N. BENANDER. 

